Yep, I've posted that article before too. Other studies show basically similar information. That's why I use 5W-30 to keep the HTHS viscosity above 3.0 cP.Low HTHS oils: the art of balancing fuel efficiency and engine protection - Q8Oils
Engine oil manufacturers are challenged to balance the fragile equilibrium between oil efficiency and reducing engine wear. Q8Oils offers low HTHS engine oils for the PCMO- and HDDO market that reduce fuel consumption while maintaining engine protection.www.q8oils.com